Impulse counter



July 19, 1949.

Filed Jan. 4, 1947 M. KALFAIAN IMPULSE COUNTER 2 Sheets-Sheet 1 AMPLIFIER FIG.1.

INVEN TOR.

July 19, 1949. My KALFMAN 2,476,303

IMPULSE COUNTER Filed Jan. 4, 1947 2 Sheets-Sheet 2 46 5O INVENTOR.

BY if 44 \48 Patented July 19, 1949 UNI TED STATES PATENT OFFICE COTTNTER Meguer Kalfaian, Asbury Park, N. 1. Application .fanuary' l, 194.7, Seriallio. 720,282 z-claimsi. (o1. 250: -27) amended April 20 The invention described herein may be manu factured and used by or for the. Government for. governmental purposes, without the payment. of any royalty thereon.

The present invention relates to electronic re laying systems, and more particularly toi-elec tronic trigger circuits which will respond to .odd shaped signal waves that may be randomly dis-- tributed within zero to a wide range ottrequene c1es.

In general practice, the counting. of l the, randomly distributed pulses .from Geiger-Muller tubes and ionization chamber have been mainly performed by a stage of the well known thyratron. or the vacuum tube scale-by two trigger circuit to divide by two, and this followed by successive stages of trigger circuits to scale down. these.

pulses at a rate at which a relatively slow.-me-

chanical recorder would operate to any desired.

efiiciency. However, the ultimate can be reached is determined by power of the first stage of the: scalin circuit The limited operating condition of. the firstzstage of the scaler or trigger circuit is that the. triggere ing action of the circuit from one equilibrium. state to the other at each incident pulse depends upon the series RC time constants. Due tothe fact that the recovery time of the condenser should be short for high speed operatinn,-,,the. circuit will not respond satisfactorily to long pulses because during the input pulse the tubes on both sides of the trigger circuit have-low impedance and will quench cross pulsesi. Then again, it is required for such operation, .th-atsther' incoming pulses should have either steep rise-or steep fall to avoid errors. This results inan other undesirable objection that, counting; imstruments of this character are subject-to some of the incoming. pulses. it they are. distributed within a wide range of frequencies-.;

Accordingly, the object of this invention ieta provide a scale-by-two circuit arrangementwherein the usually employed capacitive coupling, element is eliminated. Due to the direct coupled operation of the arrangement, the scaling-circuit is rendered responsive to odd wave shapes-lira wide range of frequenci In the preferred embodiment of theinventicm the scaling. circuit. includes a first. andna second. directly cross-coupled trigger circuit. which by further direct coupling cross control each. others state of conduction. The operating performance is such that, while the incoming signal reverses the: state of conduction of the said. second trigger circuit, the said first trigger. circuit remalnsuln the resolving.

activateduntil the said incoming signal ceases. substantiallyto a minimum, whereupon the said first trigger circuit reverses under the direct cross-controlofthe said last reversed state of the said. second trigger circuit. Due to the inherently delayed operating time interval between thesaid second and first trigger circuits, the afrangement will also. be found useful .appliz 'za-v tions where itis desired to transmitinformatioii as. to when asignal has; arrived and when it has. ceased .toa minimum.v

Afu'rther object of thelnvention isto provide: a chain arrangement of direct coupled. trigger circuits for. counting. the scaled. signals of the T aforementionedfirst stage, which incombin'ation forms a complete counting. system. H

Thennovel ,featiiresof. m invention will be more apparent to the .skill'edin theartrfrom the following detailed description with rferenceito the accompanying drawings, wherein.

Figure I is a diagramof-directly cross-coupled scaIe-by-twc relay circuits embodying. the iiiventicn.

Eigure 21s adiagram of a return chain of direct-couples rela circ'ui'tsinaccordance with theinrenuon. I

Proceeding now to a detailed description .oftl'ieinvention,. a reference is firstmade to Figure. l, which. sliowshtwo direct-coupled electronic relay, circuits. directly crossecoiipled to each otheraandfor .coinzenie'rice they are marked- Aand B. The relay circuit Acomprisesrelaytubes l :and iand exciterftubesi and l, The voltage variations across. the. plate. circuit resistance; of} tube ldirectly appliedtc the. control .gridof tube.

through the .seri'eslconnected; resistances ti and: "I while thevol'tage variations across the. plate cirdilitres'istance. .of tube 2 is. directly .-applied. tn the. control grid of tube-l through the seriesresistances i and, g A

TherelayB circuit comprises relay tubes M" and li and excitertubes l and -l 4.- Thevbltage variationsacross.the-plate. circuit. resistance: l5; (if-tube ll is directly appliedto the'control grid oftube. l2 through. the series connected resist-- anccs. l 6 and t1; while.-th e voltage variations acrossthe plate .ci-rcuit. resistance l-8 of tube l-Zis directly applied tc the control grid @o tuber ll through; the. series connected resistances. L9 t. Thelexcitertubes 3 and of; relay A arechosei-t. to havemulticdntrol elements, and: the-is plates are! connected in parallel with thecplates .01! relay tubes 1' and 2 respectively, Simila;rly, theiexciter 6i tubes; l4 ct relay "B areechosen to have multicontrol elements, and their plates are connected in parallel with the plates of relay tubes II and I2 respectively.

One of the control grids of both of the exciter tubes 3 and 4 of relay A are directly cross connected with the control grids of relay tubes II and I2 of relay B, while one of the multicontrol grids of both of the exciter tubes I3 and I4 of relay B are directly connected to the control grids of relay tubes I and 2 of relay A respectively.

The incoming signals amplified by 2I (shown in block diagram), are full wave rectified by 22, such that, all incoming signals are obtained in positive polarity, and applied to the second control grids of exciter tubes I3 and I4 of relay B simultaneously, as shown by the parallel connection of said grids.

The positive signals obtained from 22 are phase inverted by 23 (shown in block diagram) and applied in negative polarity to the second control grids of the exciter tubes 3 and 4 of relay A simultaneously, as shown by the parallel connection of said grids.

It will be noted in Figure 1, that, the series connected resistances 5, 6, 'I and 8, 9, III of relay A, and the series connected resistances I5, I8, I1 and I8, I9, 20 of relay B, act as voltage dividers across the plate potential supply 24. The voltage divisions at the control grids of relay tubes I and 2 of relay A, and the voltage divisions at the control grids of relay tubes II and I2 of relay B are normally in equal magnitudes, and since these grids are connected at positive potentials across said dividers, the cathodes of all said tubes I, 2, 3, 4 and II, I2, I3, I4, are connected in parallel and varied across said potential 24 by contact 25 until the proper desired bias potential for all said control grids is obtained. However, the bias potential for the second control grids of the exciter tubes I3 and I4 of relay B is obtained separately by contact 26, which is normally.

varied to substantially plate current cut-off of said tubes.

A normal state of conductance or non-conductance of the tubes I, 2, 3, 4 and II, I2, I3, I4 of the circuit arrangement given in Figure 1 may be assumed as follows:

Since the second control grids of the exciter tubes I3 and I4 of relay B are normally biased negatively, we may assume that these tubes have no plate current flow. Now assuming that tube II is initially conducting, the voltage across the plate circuit resistance I5 of said tube drops, and the control grid of tube I2 becomes negatively biased with respect to its cathode, and the plate current of tube I2 drops to minimum. We may therefore assume that the tube II is conducting in steady state having obtained zero bias upon its control grid, and the tube I2 is non-conducting in steady state having obtained a large negative bias upon its control grid. We observe that the control grid of tube I2 is directly connected to the first control grid of the exciter tube 3 of relay A, and accordingly the tube 3 is non-conducting. The control grid of tube II of relay B is directly connected to the first control grid of the exciter tube 4 of relay A, and since the second control grids of both 3 and 4 tubes are normally biased near to ground potential, the tube 4 conducts plate current. The voltage across the plate circuit resistance 8 drops and applies a large negative bias upon the control grid of tube l. Consequently, the tube I is non-conducting and the tube 2 is conducting in a stable state.

Now assume that a positive signal arrives at the aliases second control grids of the exciter tubes I3 and I4 to shift the bias upon said grids towards ground potential. The first control grid of tube I3 being directly connected to the control grid of tube I, and since said last named grid having initially received large negative bias, the plate current of tube I3 remains non-conducting. However the first control grid of tube I4 being directly connected to the control grid of tube 2, and since said last named grid having initially received near ground potential, the tube I4 starts conducting. The voltage across the plate circuit resistance I8 drops and applies a negative potential upon the control grid of tube II. As the plate current of tube II decreases, the voltage across the plate circuit resistance I5 increases and drives the control grid of tube I2 towards ground potential. The function being that, as the plate current of tube I I decreases, the plate current of tube I2 increases until they both reach an equilibrium. As the plate current of tube I2 increases further than said equilibrium point, the plate current of said tube suddenly assumes its highest conductance, and the plate current of tube II drops to minimum. At this triggering instant it will be noted that the bias potentials upon the first control grids of the exciter tubes 3 and 4 of relay A are reversed, by virtue of the fact that their grids are directly connected to the control grids of tubes II and I2 of relay B. However, while the incoming signal has activated the exciter tube I4 of relay B, the same incoming signal is applied to the second control grids of exciter tubes 3 and 4 of relay A in negative polarity. Therefore, while the incoming signal resides, the exciter tubes 3 and 4 of relay A remain inactivated. When the incoming signal ceases to a substantially minimum value, the second control grid of the exciter tube 3 assumes a ground or nearly ground potential, and since the first control grid of said tube has already received a ground potential from the control grid of tube I2 of relay B, the voltage across the plate circuit resistance 5 of tube I of relay A drops, and the tubes I and 2 alternate their stable conductive states. Now, the cut-off bias voltages upon the first control grids of the exciter tubes 3 and 4 of relay A, and the exciter tubes I3 and I4 of relay B are reversed, so that, when the following signal arrives the stable conductive states of relay A and relay B are reversed by the same previous performance as explained.

At the output of the circuit arrangement given in Figure l, alternate pulses are obtained at each triggering action. The signals obtained from G: and G4 will be quite near the beginning of the incoming signal, whereas, the signals obtained from G1 and G2 will be quite near the end of the arrival of said incoming signal. Because of the alternate signals obtained from the circuit arrangement given in Figure l, the following chain of scaling triggers may be devised to operate by alternate signals. Since the rise and fall of the wave-form of the output pulses of Figure 1 will be substantially uniform, even though randomly distributed, the coupling of the output of Figure l to the chain of trigger circuits may either be resistancecapacity coupling, or of direct coupling. However, for convenience, direct coupling is shown in the drawin Figure 2 shows a direct coupling chain of four trigger relay circuits, which may conveniently be marked, as, relay A comprising relay tubes 21, 28 and exciter tubes 29 and 30; relay B comprising relay tubes 3|, 32 and exciter tubes 33,

34} relay- G comprising relay tubes 35,- '36; and? eke'iter tubes 31; 38; relay D comprising relaytubes 39, 40 '-'and-exciterv tubes Al, 42;

The 'eXciter tubes- 29, 30, 3e, 34,31,315 and: 4i; #2 are chosen having double con-trol grids, however, other multicontrol tubes may be em pl'oyed; such as pentodes, in whichgcase, the supressaror screen grid-voltages may be varied as a second series controlelement for the now of plate currentsfi saidtube. This also applies to the exciter tubes inland l-3, l4iz il igur'e:1.'

The secend control grids ci the-exciter tubes 29; 3'0 and 31; -3-8*are connected; in parallel and receive a normalplate current cut-ofinegative biasii rom the plate circuit resistance 43 of' tube 44" and tlie" voltage -dividing series resistances 4'5- and Similarly, the second control grids er th'e eXci ter tubes 33; 34 and 4 l, 42- are connected in paraliehandreceive a normalplate current cnt-be negau e bias from the plate circuit res i'stanc'e 41 oftube -18- and the voltage dividing series resistances '49 and 50. The control grids of tubes and were marked G1 and G2, indieating direct coupling to the grids G1 and G2 of tubeslt a'nd; mm Fig. "1-,

'Pmaeeamg now to the chainopera'tion of; the er ially direct-coupledtrigger circuits -A, B, C and D'in Fig. *2, we willas'sume as a reference condition of the relays, such that, the relay tubes 2 8; 32; 36 and SS-a're normally conducting. We will also assume that this reference condition has been last-effected by the arrivalof a nega tive signal upon- G; of tube 48, Now, when a negatives'ignal-arrive's uponG1 of tube 44, a positivefpbt'ential; from across the plate circuit resistance 43 and the voltage dividing resistances 45fand lfiof-tubei'dd is dirctlyappiiedupon the second control grease: the e iciter tubes' -29; -30 of riajy "A, and the exciter tubes 37; -38-of relay C." it will-be noted that the 'first'controlgrids of exciter tubes 30 andf31' are directly connected to the cont rol grid of'relay tube 31 of "relay B; AI 'd s seum dbr vie n. mamm reiereneeeondition o the relays A to B the tube 31 of relay B is non-c'onductive due to allarg e negative bias received; upon its control grid by theconductive state oi relay tube '32. Accord;- ingly, the exciter tubes 30 and 31' of relays A arid 1 re ag ed i e s ia ive eventh'e first control grid of theexciter tube 29 of relay A receivesa near ground-potential by direct connection to the. control grid of conductive tube 39 of relay D fand 'a plate'current flow through the said. tube causes relayA- to trigger itscstate of conduction, such that, tube 21: becomes. iconductive and tube. 28. non-conductive.

When the following negative pulse arrives at the control grid G2 of tube'48, a positive potential from across the plate circuit resistance 41 and the voltage dividing resistances 4 9fand 50 of-tube 48is directly applied upon the second control grids of theexciter tubes-33, 34 ctr-clay B, and the exciter tubes ll, 4g-of;r elay D. The first control grid of exciter tube 33 having near gi'ounci potential by direct connectionto the-control grid -o'r"--'the conducting relay tube 2-] of "A, the tube 33-becoznes active andtiig ge'rs relay B; such that, tube 3i becomes conductive and tube 32 non-conductive. Similarly, the first control grid of the exciter tube 42 of relay D having near ground potential by direct connection to the control grid of the conducting relay tube 21 of A, becomes active and triggers the relay D, such that, tube 40 becomes conductive and tube 39 nonconductive. The ground potential across the grid 7 grid of the. exciter. tube 31: "of; relay -C, hence,

. this direct coupling pieparesxsaid exciter tubes.

to be driven conductive-when.theiollowinglnegae tive pulse arrives at G51. Whena negative pulsearrives at G1, the relaysxA andre are triggeredto new-stable states, that is, the relay tube. 2 8 of: relay it becomes conductive, and the relay tube 35 of relay (27 becomes simultaneously- C'OI'ldLIG tive. It will be noted that the negativesignal upon excitesthe second control: grids 01 the eiic'iter tube-e129 and .30 orrelay A, and the e);- citer tubes 3 and: 38 of rel'ay- G: However, the. eXciter tubes-"ra ens stare"prevented being activate'd by thenegative ent-bit potential which resides during said pulsing period at the controlgrid'of the relay tube-tlof relayD. The ground potentialdevelopedacross the'grid ci'reuit ofr'elay tube 35- of relay G-is-appli'ed to 'the lfirst control grid'o'fithe exciter tube '34 otrel'a y B and also to the first control-grid of-the exciter tube 4']; of 7 arrivalof-a negative pulse upon G2, the relay tubeflbfi relay '3 becomes conductive, and fialso the relay tubeBfl of-rel-a'y D becomes conductive whereupon, the chain counting repeats;

For convenience the suc essive relaying operti'on is marked asfollqtvs: i itia setting brinerelay ,1..."

For an initial setting of the relay, "circuits as shown above, the grid circuit resistancesil, 52, 53..and '54. ottherelay tubes .1, 3 l,, 3 5.and.4il may be short clircuiteg'ifmomentarily either by manual switches or mechanical relays.

It W1 be e teiii et Within? la i n em n (if-Figure 2; anynumber of stages ybel'added o a tielilan-aepl cat A sMhat t e direct cross-couplings oi tharelgybircuits shown i gureandi su e 2, are-e9 e anate-Pl t eu tcpu i esa l a hode yit'c ll i sma be m er e. A ariinsl gth j nrentiqno i r t e ei e e e s Pi tfiht t Scope de e .'bythe laims.

E9; m lse euntiesesr temi Bu fifilfi'bY: two impulse dividing arrangement comprising a directly cross-controlled combination of a first and second trigger circuits; each of said trigger circuits comprising a first and a second tube of the grid-controlled type so cross-coupled that while one tube is conducting it imposes a high direct-current negative voltage upon the control grid of its mate tube to render it substantially.

also to the first 'controlg 7 non-conductive, said first and second tubes of the said first and second trigger circuits in the said aforementioned arrangement having associate exciter tubes each of which having a first and a second control grid and'connected in a manner such that in the said first trigger circuit an exciter tube bearing the numeral as a third tube initiates the conductance of the second tube by direct coupling and an exciter. tube bearing the numeral as a fourth tube initiates the conductancerof the first tube by direct coupling; and in the said second trigger circuit an exciter tube bearing the numeral as a fifth tube initiates the conductance of the second tube by directcoupling and an exciter tube bearing the numeral as a. sixth tube initiates the conductance of the first tube by direct coupling, a source of signals randomly or evenly distributed in connection with the aforesaid arrangement and means therewith for applying said signals upon one of the control grids of the said fifth and sixth exciter tubes of the said second trigger circuit simultaneously in positive direction to drive said grids to near cathode potential from a normal high negativebias; and means for simultaneously applying said last mentioned signals upon one of the control grids of the said third and fourth exciter tubes of the said first trigger circuit simultaneously. in negative direction to drive said grids to a high negative bias from a normal near cathode potential, the other control grid of the said third exciter tube of the said first trigger circuit having direct coupling with the first tube of the saidsecond trigger circuit in a manner such that while said last mentioned first tube is conducting it imposes a high negative bias upon said grid of the said third exciter tube rendering it inoperative; and the other control grid of the said fourth exciter tube of the said first trigger circuit having direct coupling with the second tube of the said second trigger circuit in a manner such that while said last mentioned second tube is conducting it imposes a high negative bias upon said grid of the said fourth exciter tube rendering it inoperative, the other control grid of the fifth exciter tube of the said second trigger circuit having direct coupling with the second tube of the said first trigger circuit in a manner suchthat while said last mentioned second tube is conducting it imposes a high negative bias upon said grid of the said fifth exciter tube rendering it inoperative; and theother control grid ofthe said sixth exciter tube of the said second trigger circuit having direct coupling with the first tube of the said first trigger circuit such that while said last mentioned first tube is conducting it imposes a'high negative bias upon the said grid of the saidsixth exciter tube rendering it inoperative, whereby by the said manner of direct cross-coupling of the said first and second trigger circuits at triggering performance is effected such that while the aforesaid incoming positive signal reverses the said second trigger circuit under the direct crosscoupled guidance of the said first trigger circuit the said first trigger circuit remains inactivated by the reception of the said last mentioned signal in negative direction until'the said signal decreases substantially whereupon the said first triggercircuit reverses under the control of the said last reversed stateof the said second trigger circuit, and the incoming signals alternate in an outgoing circuit or circuits for chain counting.

2. In animpulse counting arrangement the combination of a direct coupled chain of trigger circuits, a first stage of a scale-by-two circuit as in claim l fortransforming the incoming random signals into signals of alternate polarities in outgoing firstand second channels, in the aforesaid chain each trigger circuit comprising a first and a second tube of the grid controlled type so cross coupled that while one tube is conducting it imposes a high direct-current negative voltage upon the control grid of its mate tube torender it substantially non-conductive, said first and second tubes being associated with exciter tubes; each having a first and a second control grid and connected in a manner such that an exciter tube bearing the numeral as a third tube initiates the conductance of the said second tube by direct coupling and an exciter tube bearing the numeral as a fourth tube initiates the conductance of the said first tube by direct coupling, means for applying the alternate signals from the aforesaid first channel to the said second control grids of the said third and fourth exciter tubes of every second succeeding trigger circuit in the said chain; and means for applying the alternate signals from the aforesaid second channel to the said second control grids of the said third and fourth exciter tubes of every other succeeding trigger circuit in the said chain, a direct coupling of the circuit of the second tube in each succeedingtrigger stage to the aforesaid first control grids of the fourth exciter tube in a preceding stage and to the third exciter tube in a succeeding stage in a manner such that while said second tubes are conducting the said controlled exciter tubes become inoperative respectively, whereby by the said manner of direct intercouplings a relaying action is efiected such that while one trigger stage reverses its state of conduction it causes a trigger circuit preceding two stages to reverse conduction and while simultaneously the aforesaid trigger stage prepares a succeeding trigger stage for reversal when the following alternate signal arrives.

MEGUER KALFAIAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Review of Scientific Instruments, vol. 14, June 1943, An Improved Cosmic-Ray Radio Sonde, by Pickering, pp. 171-173. (Copy in Div. 10.) 

